Private Branch Exchanges (PBXs) are becoming increasingly complex, and offer a user a variety of sophisticated features. Many of the offered features are implemented with little or no user interaction because the PBX includes a number of internal processes responsive to specified conditions to automatically activate several of the features. An example of one such feature is automatic call forwarding. Automatic call forwarding occurs when an incoming call is received at a station and is not answered. The incoming call is automatically forwarded following a specified number of rings to a cover station where the call can then be answered. The automatic call forwarding feature is not burdensome to the user because the PBX utilizes an internal monitoring scheme for detecting the specified number of rings and, then, automatically implements the cover function without user interaction. There still exists, however, a number of PBX operations that excessively burden the user.
One such operation that may be burdensome is the establishment of a call connection outside the PBX. To establish an outside call connection, a calling party must first gain access to a Central Office (C.O.) and then, the C.O. must be available to serve the call. The calling party gains access to a C.O. by dialing an access code, typically a "9". The PBX, responds to the dialing of the "9" and accesses the C.O. by seizing a trunk port of the PBX. The C.O. indicates its availability by generating a dial tone and applying the dial tone to the calling PBX station. The calling party may now dial the digits of a destination or called station. The calling party at the calling station remains "off-hook" and aurally monitors the receiver of the requesting station while waiting for the receipt of C.O. dial tone. In the United States and certain other countries having advanced telecommunication systems, C.O. dial tone is received in a relatively short time period, e.g. 2 seconds. However, in certain other countries having less than optimal telecommunication systems, the receipt of C.O. dial tone may take several minutes, e.g. 30 minutes. Therefore, aural monitoring for C.O. dial tone by the calling party may be burdensome on the calling party since aural monitoring requires the calling party to remain "off-hook" for an indeterminate period of time and prevents the calling party from pursuing other activities during this time. Heretofore, no arrangement exists which relieves a calling party from aural monitoring for C.O. dial tone.